Methods and systems for controlling a prosthetic or orthotic device
A prosthetic or orthotic device (POD) can include first and second limb members coupled at a joint, an actuator, and a controller. The actuator can be configured to actuate the first limb member relative to the second limb member. The controller can cause the actuator to exhibit a force rejection behavior during a portion of stance phase and cause the actuator to exhibit a force following behavior during a portion of swing phase. The controller can, based on a determination that a gait parameter satisfies a gait parameter threshold, cause the actuator to at least one of: apply a first torque at the joint to cause the POD to flex during a portion of stance phase, decelerate flexion of the POD during at least a first portion of the swing phase, or decelerate extension of the POD during at least a second portion of the swing phase.
1 . A prosthetic or orthotic device comprising:
a first limb member;
a second limb member coupled to the first limb member at a joint;
an actuator coupled to the first limb member and the second limb member and configured to actuate the first limb member relative to the second limb member; and
a controller configured to control the actuator, the controller further configured to:
based at least in part on a determination that a gait parameter does not satisfy a gait parameter threshold, select a passive mode for a controller mode of the controller, wherein in the passive mode, the controller causes the actuator to exhibit a force rejection behavior during at least a portion of stance phase and exhibits a force following behavior during at least a portion of swing phase, and
based at least in part on a determination that the gait parameter satisfies the gait parameter threshold, select an active mode for the controller mode, wherein in the active mode, the controller:
causes the actuator to exhibit a force rejection behavior during at least a portion of stance phase and exhibit a force following behavior during at least a portion of swing phase, and
causes the actuator to exhibit at least one of a toe-off assist behavior, a braking behavior, or a bumper avoidance behavior at a power level, wherein the power level varies in proportion with the gait parameter.
2 . The prosthetic or orthotic device of claim 1 , wherein the controller causes the actuator to exhibit at least two behaviors of the toe-off assist behavior, the braking behavior, and the bumper avoidance behavior based on a determination that the gait parameter satisfies the gait parameter threshold.
3 . The prosthetic or orthotic device of claim 1 , wherein the gait parameter threshold is a first gait parameter threshold, wherein the controller causes the actuator to exhibit at least two behaviors of the toe-off assist behavior, the braking behavior, and the bumper avoidance behavior based on a determination that the gait parameter satisfies a second gait parameter threshold.
4 . The prosthetic or orthotic device of claim 1 , wherein the gait parameter threshold is a first gait parameter threshold, wherein the controller causes the actuator to:
exhibit at least one behavior of the toe-off assist behavior, the braking behavior, and the bumper avoidance behavior at a first power level based on the determination that the gait parameter satisfies the first gait parameter threshold, and
exhibit at least one behavior of the toe-off assist behavior, the braking behavior, and the bumper avoidance behavior at a second power level based on a determination that the gait parameter satisfies a second gait parameter threshold.
5 . The prosthetic or orthotic device of claim 1 , wherein the controller is further configured to determine a first torque at the joint, and wherein to cause the actuator to exhibit the force rejection behavior, the controller causes the actuator to apply a second torque at the joint, wherein the second torque is equal to and opposite the first torque, and wherein the first torque corresponds to a force applied to the prosthetic or orthotic device by a user.
6 . The prosthetic or orthotic device of claim 1 , wherein in the active mode, the actuator exhibits the force rejection behavior during at least a portion of the stance phase between foot strike and midstance.
7 . The prosthetic or orthotic device of claim 1 , wherein the controller is further configured to determine a first torque at the joint applied to the joint by a user, and wherein to cause the actuator to exhibit the force following behavior, the controller causes the actuator to apply a second torque at the joint, wherein the second torque is in a same direction as the first torque.
8 . The prosthetic or orthotic device of claim 1 , wherein in the active mode, the controller causes the actuator to exhibit the force following behavior during at least a portion of the swing phase between toe off and a heel rise target.
9 . The prosthetic or orthotic device of claim 1 , wherein in the active mode, wherein the controller causes the actuator to exhibit the toe-off assist behavior, the toe-off assist behavior occurs during at least a portion of the stance phase between midstance and toe off.
10 . The prosthetic or orthotic device of claim 1 , wherein in the active mode, the controller is configured to:
based on a determination that a heel associated with the prosthetic or orthotic device has reached a first heel rise target, control the actuator to decelerate flexion of the prosthetic or orthotic device until the heel reaches a second heel rise target.
11 . The prosthetic or orthotic device of claim 10 , wherein in the active mode, the controller is configured to:
based on a determination that the heel has reached the second heel rise target, cause the actuator to exhibit the force following behavior.
12 . The prosthetic or orthotic device of claim 1 , wherein the prosthetic or orthotic device is a powered knee, and wherein in the active mode, the controller is configured to:
based on a determination that a knee angle satisfies a first knee extension target, control the actuator to decelerate extension of the joint until the powered knee reaches a second knee extension target.
13 . The prosthetic or orthotic device of claim 1 , wherein the prosthetic or orthotic device comprises of a sensor module configured to obtain gait parameter data associated with the prosthetic or orthotic device, and wherein the gait parameter data corresponds to a gait parameter, wherein the gait parameter comprises at least one of user forward speed, walking cadence, stance time, thigh angle excursion amplitude during stance phase, absolute thigh angle at toe-off, absolute thigh angle at foot strike, knee torque amplitude at late stance, number of steps completed while achieving a minimum swing flexion amplitude, thigh or shank sagittal plane rotational or linear acceleration, thigh or shank sagittal plane rotational speed amplitude, ground reaction force amplitude at foot strike, ground reaction force amplitude on toe in late stance, user center of mass linear acceleration, a ground interaction, a shank angle, or a joint angle.
14 . The prosthetic or orthotic device of claim 1 , wherein the controller mode transitions from the passive mode to the active mode based at least in part on a determined activity of a user.
15 . A prosthetic or orthotic device (POD) comprising:
a first limb member;
a second limb member coupled to the first limb member at a joint;
an actuator coupled to the first limb member and the second limb member and configured to actuate the first limb member relative to the second limb member; and
a controller configured to control the actuator, the controller further configured to:
cause the actuator to exhibit a force rejection behavior during at least a portion of stance phase,
cause the actuator to exhibit a force following behavior during at least a portion of swing phase, and
based on a determination that a gait parameter satisfies a gait parameter threshold, further cause the actuator to exhibit at least one behavior of: apply a first torque at the joint to cause the POD to flex during at least a portion of stance phase, decelerate flexion of the POD during at least a first portion of the swing phase, or decelerate extension of the POD during at least a second portion of the swing phase, wherein the actuator exhibits the at least one behavior at a power level that varies in proportion with the gait parameter.
16 . A prosthetic or orthotic device (POD) comprising:
a joint; and
a controller configured to:
receive gait parameter data; and
select an active mode or a passive mode based at least in part on the gait parameter data;
wherein in the passive mode, the controller causes an increase in resistance at the joint during stance phase and causes a decrease in resistance at the joint during swing phase, and
wherein in the active mode, the controller causes:
an increase in resistance at the joint during a first portion of the stance phase,
a decrease in resistance at the joint during a second portion of the stance phase,
a decrease in resistance at the joint during at least a first portion of the swing phase,
an increase in resistance at the joint to decelerate flexion of the POD during at least a second portion of the swing phase, and
an increase in resistance at a third portion of the swing phase to decelerate extension of the POD during at least a third portion of the swing phase.
17 . The prosthetic or orthotic device of claim 16 , wherein the POD further comprises a non-motorized actuator coupled to the joint and configured to apply torque to the joint, and wherein the controller causes an increase in resistance by increasing a resistive braking effect and causes a decrease in resistance by decreasing a resistive braking effect.
18 . The prosthetic or orthotic device of claim 17 , wherein the non-motorized actuator is a magnetorheological fluid actuator.
19 . The prosthetic or orthotic device of claim 16 , wherein the POD further comprises a motorized actuator coupled to the joint and configured to apply torque to the joint, and wherein the controller causes an increase in resistance by causing the motorized actuator to apply torque to the joint in an opposite direction of a determined torque at the joint and causes a decrease in resistance by causing the motorized actuator to apply torque to the joint in a same direction as a determined velocity of the joint.